Triazine containing azo dyestuffs



United States Patent 3 186 9% rnmzm'n coisransn so AZU nvasrnrrs Alvin C. lithe, Buffalo, NE assignor to Ailied Chemical gorporation, New York, N.Y., a corporation of New oris No Drawing. Filed Dec. 12 195%, Ser. No. 75,195

9 Claims. (Cl. 266-157) g This invention relates to novel monoazo dyestuffs containing a triazine nucleus, and more particularly to naphthotriazostilbene dyestufis.

The novel dyestuffs of the present invention have the general formula wherein R represents a naphthalene radical fused to the triazole ring in the l,2-positions as indicated by the valence bonds, R is an alykyl or aryl radical, R is an aryl radical, M is a cation, and the total number of sulfonic acid groups in the dyestuff does not exceed four.

The naphthalene radical (R) and the aryl nuclei (R and R of the acylacetarylide component may contain one or more non-chrornophoric substituents. The nonchromophoric substituents include members selected from the group consisting of hydrogen, lower (i.e., one to eight carbon atoms) alkyl, lower alkoxy, hydroxy, halogen, carboxylic acid and its salts and functional derivatives, e.g., esters, amides, and nitrile, and finally sulfonic acid and its salts and functional derivatives, e.g., esters, amides and sulfones.

Upon addition to cellulosic materials, these novel dyes generally yield pure, greenish-yellow tints, possess a very good afiinity for cellulose fibers, and produce dyeings having excellent properties of fastness to wet process ing and light. In addition, these novel dyestuffs are particularly distinguished by the completeness of their dischargeability with common bleaching agents, and by the brilliance of their yellow color when exposed to ultraviolet radiation.

Properties such as these have made these novel dyes admirably suitable for the dyeing of paper. In particular, dyes which possess that property of complete dischargeability of color under the effect of bleaching agents, are of especial value in modern paper making practice. With the utilization of these dyes, wastes from colored paper manufacturing can be completed discolored so that wastes of several different colors can be combined and reused. An obvious economic advantage can be derived from the recovery of such waste stock.

I have discovered that the novel compounds of this invention can be produced by diazotizing an aminonaphthotriazostilbene of the general formula novel substantive dyestuffs. These intermediates are prepared in a known manner. For example, 4-amino-4'- nitrostilbene-2,2'-disulfonic acid is diazotized and coupled with an aminonaphthalene molecule which is capable of coupling in a position ortho to the amino group. The resulting ortho amino azo coupling product is treated with an oxidizing agent, e.g., sodium hypochlorite, copper salts, chlorine and the like, to produce the corresponding nitronaphthotriazostilbene. The nitro group of this product is then reduced to the amine, for example, by treatment with a reducing agent such as iron, zinc or Na S. In this manner, a large number of aminonaphthalenes have been converted to the corresponding 4- amino-4'-(l",2"-naphthotriazostilbene) 2,2 disulfonic acid. The following can be cited as typical examples. 2-naphthylamine 1-naphthylamine-4-sulfonic acid Z-naphthylamine-5-sulfonic acid 2-naphthylarnine-6-sulfonic acid Z-naphthylamine-7-sulfonic acid Z-naphthylamine-3,6-disulfonic acid 2-naphthylamine-5,7-disulfonic acid 2-naphthylarnine-6,8-disulfonic acid 1-amino-4-ethoxynaphthalene 2-amino-3-amoxynaphthalene Z-amino-6-chloronaphthalene 2-amino-6-isobutylnaphthalene Those dyestuffs in which the napthotriazine nucleus con tains at least one, and especially two sulfonic acid sub stituents are preferred in view of their superior dyeing characteristics.

The coupling reaction involving the naphthylamine and diazotized aminostilbene is best carried out in a mildly acidic medium at a pH of about 4 to about 6.8. Acidic conditions such as these favor coupling in the desired ortho position to the amino group of the naphthylamine.

Oxidation of the ortho amino-azonaphthalene to the corresponding triazine can be accomplished with a variety of mild oxidizing agents. Formation of the triazine ring is preferably effected by means of ammoniacal solutions of copper salts, e.g., ammoniacal cupric sulfate. In addition, alkaline hypohalite solutions such as, sodium hypochlorite and sodium hypobroinite can be used.'

The novel dyestufis of my invention are prepared by coupling a diazotized 4-amino-4'(l",2"-naphthotriazostilbene)-2,2'-disulfonic acid with an acylacetarylide. Preferably, the aryl nucleus is a phenyl group and contains at least one additional substituent such as an alkyl, alkoxy, halogen, trifiuoromethyl, nitrile, or sulfonic acid group. Of especial value are those acylacetanilides containing an alkoxy group in the ortho position to the amide group.

The following acylacetarylides are mentioned as typical examples of this class of coupling components: Acetoacetylaminobenzene 4-acetoacetylaminobenzenesulfonic acid Acetoacetyl-2-aminonaphthalene Z-ethoxy-1-acetoacetylaminobenzene 4-methoxy-l-acetoacetylaminobenzene Z-ethoxy-4-trifluoromethyl-l-aoetoacetylarninobenzene 2-methoxy-5-ethyl-l-acetoacetylaminobenzene 2-cyano-1-acetoacetylaminobenzene 2-bromo-6-methyl-l-acetoacetylarninobenzene 2,4-dimethyl-l-acetoacetylaminobenzene 2-ethoxy-4-bromo-S-methyl-l-acetoacetylaminobenzene 2ethoxy-4-chloro-6-methyl-1-acetoacetylaminobenzene Z-methoxy-6-trifluorornethyl-l-acetoacetylaminobenzene 2-ethoxy-4-trifluoromethyl-l-acetoacetylaminobenzene Benzoylacetylaminobenzene In accordance with a preferred mode of carrying out the 3 preparation of the novel compounds of this invention, equimolecular proportions of diazotized 4.-amino-4'-nitro stilbene-2,2'-disulfonic acid and a napththylamine sultonic acid, e.g., Z-aminonap thalene3,6-disulfonic acid, are coupled in a weakly acid medium. The coupling mass is heated to about 70 C., and is then made alkaline to Brilliant Yellow test paper with an inorganic alkali, e.g., soda ash, potassium hydroxide or trisodium phosphate. The aminoazo product is isolated by salting it out of solution, and then filtering the precipitate from the mother liquor.

The isolated aminoazo compound is slurried in hot water and an ammoniacal solution of a copper salt is added. The mixture is boiled under refluxing conditions for about 24 hours, filtered to remove insoluble material, and isolated by the addition of salt and then cooling.

The filtered naphthotriazine product is dissolved in hot, dilute, aqueous mineral acid and the nitro group is reduced to the amine, e.g., by the addition of iron, sodium sulfide, or zinc. The aminostilbenetriazine, product is isolated by neutralizing the the reduction reaction mixture, salting out, and filtering. v

The isolated product is slurried in water and then diazotized in the conventional manner. The diazonium salt is coupled in a strongly alkaline medium (alkaline to Brilliant Yellow paper) with an acylacetarylide, preferably one bearing a lower alkoxy group in the ortho position of the aryl nucleus, e.g., Z-methoxy-l-acetoacetylaminobenzene. When the coupling iscompleted, usually after'lO to 24 hours, the product is salted out and isolated in a conventional manner.

The resultant dyestulf is obtained in the form of its sodium salt. The product can be converted to its free acid form by dissolving the sodium salt in water and adding an acid, e.g., sulfuric acid, hydrochloric acid, formic acid, until the mixture reacts distinctly acid. Thereafter evaporation of the mass to dryness yields the dyestuff in the free acid form. Similarly the sodium salt of the dyestutf can be converted to other salts, e.g., salts of other metals such as potassium, calcium, manganese, magnesium, aluminum, chromium or organic amine salts such .as those derived from dioctyl amine, guanidine, amino morpholine, by dissolving the sodium salt in hot water,

acidifying the solution and adding at least the stoichiometric amount, but preferably an excess of a soluble salt of the desired metal or organic amine. Thereafter the mix ture is cooled to precipitate the salt, if insoluble, or the mass can be evaporated to dryness.

The sodium salt can also be converted to the free acid by suspending the salt in an organic solvent, e.g., methylene chloride, or acetone, and bubbling gaseous hydrochloric acid into the suspension to liberate the free acid form of the dyestuff which dissolves in the solvent, and sodium chloride which can be separated by filtration. The solvent solution of the free acid can be used directly or evaporated to dryness to obtain the free acid in solid form. Alternatively, the solvent solution can be admixed with an amine and the resultant amine salt can be obtained by wherein R represents a naphthalene radical fused to the triazole ring in the 1,2-positions as indicated by the valence bonds, R represents an alkyl or aryl radical, R is an aryl radical, and R, R and R contain one or more non-chromophoric substituents selected from the group consisting of hydrogen, lower alkyl, lower a koxy, hydroxy, halogen, carboxylic acid, ester, amide, nitrile, sulfonic acid, sulfonic acid ester, sulfone and sulfonamide, M is either hydrogen or one of the cations derived from the variety of inorganic and organic salts which can be prepared as suggested hereinabove, and the total number of'sulfonic acid groups in the dyestufr" molecule does not exceed four.

Preferably, the cation should be such as to provide a dyestuif soluble in water to the extent of one part in 200 parts by weight of the water. Especially desirable are those naphthotriazostilbene dyestuffs in which M is either an alkali metal oran ammonium cation.

The preferred dyestuffs from naphthotriazostilbene are generally light yellow powders which are easily soluble in water. These compounds dye cellulose fibers bright greenish to reddish yellow shades; Under ultraviolet light they fluoresce as a brilliant yellow color.

The following specific examples will illustrate the present invention. The temperatures are given in degrees centigrade and the parts and percentages are by weight.

EXAMPLE 1 e The sodium salt of 4-amino4'-nitrostilbene-2,2-disulfonic acid (44.4 parts) was diazotized in the conventional manner, and the diazonium salt was coupled in a weakly acidic medium at pH 5.5, with 2-amino-naphthalene-3,

G-disulfonic acid (30.3 parts).

tion was added a solution prepared from 50 parts of copper sulfate pentahydrate, 66.5 parts of 28 percent aqua ammonia and 200 parts of water. The resultant mixture was heated to boiling, and boiled under reflux for a maximum of 24 hours. The mass was filtered, the residue discarded, and the clarified filtrate was salted,'cooled and fdtered again.

The filter cake of 4-nitro-4'-(1",2"-naphthotriazostilbene)2,2',3",6-tetrasulfonic acid thus obtained was reslurried in 1500 parts of water, and 34.8 parts of 20 B. hydrochloric acid were then added. The mixture was heated to 98-100", and 40 parts of iron powder (60 mesh) were then added as rapidly as the foaming of the mixture would permit. The reduction mixture was heated at just below boiling for two hours, rendered alkaline to Brilliant Yellow test paperby the addition of sodium carbonate, and then filtered to remove insoluble material. The clari fied filtrate was salted, cooled and filtered.

The filter cake of 4-amino-4-(1",2-naphthotriaz0stilbene)-2,2,3,6"-tetrasulfonic acid was reslurried in 500 parts of water. After the addition of 29 parts of 20 B. hydrochloric acid, sufiicient ice was added to cool the mixture to 10". An aqueous solution of sodium nitrite was added to the mass during two hours, and the mixture was agitated until no free nitrous acid could be detected. The resultant diazonium salt solution was added to a mixture consisting of 22 parts of Z-methoxy:l-acetoacetyl-amino- CH EXAMPLE 3 5:0 In a similar manner to that described in Example 1 p above, Z-amino-S-methoxynaphthalene-6-sulfonic acid Was \T converted into 4-amino-4-(8"-meth0xy-1",2-naphthotri- 5 a o n o I l N 80311 803E gm azostilbene) 2,2 6 trisulfonic acid of the formula i 0on3 1F IT CH=CH-@Nfh so H CH 6: 0 a N sonar SOBH 10 i1 d precipitated from the coupling solution and was isolate 5035 y filtration and dried- T feslllliflgflyesmfi 3 Yellow This product wasrdiazotized and coupled into Z-methpowder, and dyes cellulosic fibers 1n bright greenish-yellow Oxy;1 acetoacetylkaminobenzene to produce a new d t ff shades which fiuoresce strongly when exposed to ultra- 4- 4' z" i 2 -2' i lf i b violet light. Paper dyed Wlth this dyestuif can be com z'm h t mnil-ide-6-sulfonate, of the formula pletely discharged of color by the addition of sodium (,j h f g -a jdfor hypochlorite. CH3

1 EXAMPLE 2 In an analogous manner to that described above, 4-ami- OCHR NN no-4'-(1",2"-naphthotriazostilbene) 2,2,6" trisulfonic rh=0 acid was diazotized and coupled into Z-methoxy-l-aceto- 303E 503E acetylaminobenzene. The resulting product, 4-[ 4'-(:1, I 2"-naphthotriazo) 2,2 disulfostilbene]azo-(2-meth- OOH, oxy)acetoacetanilide6"-sultonate, dyes paper in yellow S0311 shades. The dyed paper is again distinguished by the completeness with which the color can be removed by bleaching, and by the brilliance of fluorescence which results on Thi d t i a ll powder hi h d d paper in eXpOsuIe t0 ultra-Violet fight- This dyestufi in the {We yellow shades, redder in hue than the dyestufi of Example acid form has the formula 1. Paper dyed with the dyestuif of this example was com- CH3 pletely discharged of color by treatment with sodium hypo- I ehlorite solutions. The dyed paper, when illuminated with f ultra-violet light, fiuoresced strongly in brilliant yellow N-N CH=CH N=NCH Shades \I ';=O EXAMPLES 4 T0 7 N 303E 1 The procedure of Example 1 is followed in preparing I several other similar dyestuffs which also dye cellnlosic 40 materials. Once again, the color of the dyed material is SOZH discharged by treatment with sodium hypochlorite. The structure of these additional dyestuffs in the free acid form is indicated in Table I.

Table 1 Aminonaphthalene component Example used to prepare Aeetoecetylerylide coupling component Coupling shade naphthotriazost-ilbene NH: O CHzCHg t l 4 CHaC-CH2C Green-yellow.

; l CH3 -o1 S OaH OCHzCH; t l 5 NH: 01130 oHr-og- Red-yellow.

SOsH- SOaH ON OCHs i i 6 H053 NHs CHaCCHz-C Green-yellow.

o0m SOQH i i 7 NH: CHaCCHzC- Do.

SOaH "OPE 7 EXAMPLE 8 I minutes with 250 parts (by volume) of bleached sulfite pulp containing 3 parts of pulp (dry Weight). Thereafter 4 parts (byvol-ume) of 3 percent starch solution, and a like amount of percent alum solution were added. The mixture was agitated for 20 minutes, diluted to 2000 parts (by volume) by the addition of water, and finished into paper in a conventional manner. B. Bleachability test.Strips /4" X 4"), of paper prepared as above, were immersed intoa 50 ml. graduated cylinder containing an aqueous 5.25 percent sodium hypochlorite solution. After 10 minutes, the bleached strips were removed and dried in air. The color was completely discharged from the strips indicating the susceptibility of the dyestuif to the discoloring action of bleaching agents. 7

While the above describes the preferred embodiments of the invention, it will be understood that departures may be made therefrom within the scope off the specification and claims.

I claim:

, 1. A monoazo dyestufi of the formula HOzB- OOH:

wherein V v R as a member selected from the group consisting of methyl and phenyl, i

R is a member selected from the group consisting of the benzene radical, the naphthalene radical, and substituted benzene radicals containing one to three substituents selected from the group consisting of lower al-kyl, lower alkoXy, trifluoroalkyl, nitrile, chlorine, bromine and $0 M, V X is a substituentselected from the group consisting of hydrogen, lower alky1, lower alkoxy and SO M, n is'an integer from 1 to 6, and.

M is' a cation,

7 said dyestufi having a maximum ofV fourVfiQQ M groups;

2. A monoazo dyestuff which in the free acid form is 4- [4'-(1",2:' naphthotri-azo) 2,2 -disulfostilbene1azoacetoacetanilide sulfonic acid having a lower alkoxy group as sole additional substituent, in the anilide radical, and

as defined in claim Bin which radical in 6 position.

5. The monoazo dyestutf having in the free acidtorm the formula I OOH;

SO H

' 6. The monoazo dyestuif having in the free acid form the formula 0 a 4' i G-CH:

O CH;

7. The monoazo dyestuff having in the free acid form the formula 0 i-on;

I OCH;

8. The monoazo dyestuff having in the firee acid form the formula NH S0315! s mH g 9. The monoazo dyestufi having in the free acid form the formula References Cited by the Examiner UNITED STATES PATENTS CHARLES B. PARKER, Primary Examiner L. ZITVER, Examiner. 

1. A MONOAZO DYESTUFF OF THE FORMULA 